Color filter forming substrate, method of manufacturing same and display device

ABSTRACT

A color filter forming substrate used in a multifunctional terminal is provided which has a frame disposed surrounding respective colored layers for a color filter and having a non-display area formed by the frame portion all around a boundary between the display area and the frame, and specifically has a transparent substrate as a base material; and, on one side of the base material, colored layers of respective colors for a color filter disposed in a display area and a frame portion comprising a light-shielding colored layer disposed as a region not for display around a periphery of the region for display. The color filter forming substrate is used for a display device.

FIELD OF THE INVENTION

The present invention relates to a color filter forming substrate usedfor a display device, a method of manufacturing the same, and a displaydevice. More particularly, the present invention relates to a colorfilter forming substrate, comprising: a transparent substrate as a basematerial; and, on one side of the base material, colored layers ofrespective colors for a color filter disposed in a region for displayand a light-shielding colored layer referred to as a frame portiondisposed as a region not for display around a periphery of the regionfor display; and the color filter forming substrate is used for adisplay device; and when the color filter forming substrate is used fora display device, it can solve a defect that the frame portion in anon-display area surrounding a display area looks brighter than thedisplay area at the time display of the display device is turned off.

BACKGROUND ART

In recent years, display devices are becoming remarkably popular and,among them, liquid crystal display devices are widely used as a flatdisplay panel.

Generally, the liquid crystal display device has a structure where acolor filter forming substrate having a black matrix layer comprising alight-shielding colored layer and colored layers of respective colorsdisposed on one side of a transparent substrate, and a counter electrodesubstrate (also referred to as “TFT substrate”) are disposed opposite toeach other with a prescribed space, wherein liquid crystal wasencapsulated. A color image is displayed by controlling lighttransmittance of pixels of the colored layers of respective colors byelectrically controlling orientation of the liquid crystal.

In such a liquid crystal display device, quality of the color filterforming substrate governs display quality itself.

On the other hand, recently, multifunctional terminals (also referred toas high-performance terminals) are spreading extensively and tablet-typemultifunctional terminals are also expected to spread rapidly. Whileliquid crystal display devices are being used as a display of theseterminals, high display quality and good design characteristics arerequired of the display devices.

For example, there is a case where a tablet-type multifunctionalterminal is using a color filter forming substrate 110 for a displaydevice comprising: as shown in FIG. 6A, a transparent substrate as abase material 111; and, on one side of the base material 111, coloredlayers 113 of respective colors for a color filter disposed in a regionfor display 113S and a light-shielding colored layer referred to as aframe portion 112 disposed as a region not for display around aperiphery of the region for display 113S.

FIG. 6A is a plan view of a conventional color filter forming substrate;FIG. 6B and FIG. 6C are views taken in directions of arrows along E1-E2and E3-E4, respectively, in FIG. 6A; FIG. 6D is an enlarged view of theE5 portion of FIG. 6A; and FIG. 6E is an enlarged view of the E6 portionof FIG. 6A.

FIG. 7 is a plan view of a tablet-type multifunctional terminal 120which uses the color filter forming substrate 110 shown in FIGS. 6A to6E.

And, usually, the colored layers of respective colors for the colorfilter, the colored layer for the black matrix, and the colored layerfor the frame portion have been formed by photolithography processes.And the frame portion 112 and the black matrix (not shown in the figure)have been formed together by the same photolithography process.

The tablet-type multifunctional terminal 120 usually uses the colorfilter forming substrate 110 shown in FIGS. 6A to 6E, where the side ofthe base material 111 comprising a transparent substrate faces the sideof a frame 121 and a part of the frame portion 112 corresponds to thenon-display area 123. A display area 122 and the non-display area 123 ofabout 1 mm width are so designed that they are visible from a viewer'sside through an opening inside the frame 121.

The main reasons why the width of the non-display area 123 is designedto be about 1 mm as just described are to make the whole display areasurely visible from a viewer and to provide some latitude in positionalaccuracy between a display panel using the color filter formingsubstrate 110 and the frame.

However, in the tablet-type multifunctional terminal 120 shown in FIG.7, when display on the display area 122 is turned off, a region of theframe portion, which is the non-display area 123 around the display area122, looks brighter than the display area 122, resulting in a distinctdifference between the display region 122 and the non-display area 123.This diminishes the visual quality and has been a problem.

Additionally, in the above, explanations were made mainly with referenceto liquid crystal display devices as an example. However, theabove-mentioned problem is not limited to the liquid crystal displaydevices but may occur similarly to any display device which uses a colorfilter forming substrate having a frame portion in a region not fordisplay around a periphery of a region for display.

PRIOR ART DOCUMENTS Patent Document

Patent Document 1: International Publication No. WO 2010/150668

Patent Document 2: Japanese Patent Laid-Open Publication No. 2009-053893

SUMMARY OF INVENTION Problems to be Solved by the Invention

As described above, recently, the multifunctional terminals arespreading extensively and, especially, the tablet-type multifunctionalterminals are also expected to spread rapidly. While liquid crystaldisplay devices are being used as a display of these terminals, highdisplay quality and good design characteristics are required for thedisplay devices.

Under these circumstances, when, in a multifunctional terminal, a colorfilter forming substrate for a display device is being used as shown inFIG. 6A, the color filter forming substrate comprising a transparentsubstrate as a base material and, on one side of the base material,colored layers of respective colors for a color filter disposed in aregion for display and a light-shielding colored layer referred to as aframe portion disposed as a region for not display around a periphery ofthe region for display, there has been a defect that, when display inthe display area is turned off, the frame portion as a non-display areasurrounding the display area looks brighter than the display area,resulting in a distinct difference between the display area and thenon-display area, and poor visual quality. A countermeasure to thisproblem has been desired.

The present invention is intended to address this problem and tries toprovide a color filter forming substrate of good visual quality byreducing the difference between the display area and the frame portionas the non-display area surrounding the display area, which differencearises when display is turned off when a color filter forming substratefor a display device is being used in a display device, in which thecolor filter forming substrate comprising a transparent substrate as abase material, and, on one side of the base material, colored layers ofrespective colors for a color filter disposed in a region for displayand a light-shielding colored layer referred to as a frame portiondisposed as a region not for display around a periphery of the regionfor display.

Means for Solving the Problems

The color filter forming substrate of the present invention comprises: atransparent substrate as a base material; and, on one side of the basematerial, colored layers of respective colors for a color filterdisposed in a region for display and a light-shielding frame portiondisposed as a region not for display around outside of the region fordisplay; and the color filter forming substrate is used for a displaydevice, wherein the frame portion has a reflection controlling layer anda light-shielding colored layer laminated in this order from the basematerial side.

Further, the present invention is the above-mentioned color filterforming substrate, wherein the above-mentioned reflection controllinglayer is a colored layer and wherein the colored layer which is theabove-mentioned reflection controlling layer comprises at least one ofthe colored layers of respective colors for the color filter.

Furthermore, herein, when the color filter forming substrate is used fora display device, the region which becomes a display area is referred toas a “region for display” and a region which does not become the displayarea is referred to as a “region not for display.”

Also, the present invention is the color filter forming substrateaccording to any of the above-mentioned descriptions, wherein thereflection controlling layer comprises the same one colored layerdisposed as a single layer.

Alternatively, the present invention is the color filter formingsubstrate according to any of the above-mentioned descriptions, whereinthe reflection controlling layer comprises a plurality of differentcolored layers disposed in parallel as a single layer.

Further alternatively, the present invention is the color filter formingsubstrate according to any of the above-mentioned descriptions, whereinthe reflection controlling layer comprises a plurality of differentcolored layers disposed as a laminate.

The method for manufacturing the color filter forming substrate of thepresent invention is a method for manufacturing a color filter formingsubstrate, the color filter forming substrate comprises: a transparentsubstrate as a base material; and, on one side of the base material,colored layers of respective colors for a color filter disposed in aregion for display and a light-shielding frame portion disposed as aregion not for display around outside of the region for display; thecolor filter forming substrate is used for a display device; the frameportion has a colored layer for a reflection controlling layer and alight-shielding colored layer laminated in this order from the basematerial side, wherein the colored layers of respective colors for thecolor filter, a light-shielding colored layer for a black matrix whichseparates the colored layers of respective colors, the colored layerwhich becomes the reflection controlling layer of the frame portion, andthe light-shielding colored layer of the frame portion are each formedby one photolithography process; wherein the whole colored layer whichbecomes the reflection controlling layer of the frame portion is formedin at least one of respective photolithography processes for forming thecolored layers of respective colors for the color filter; and whereinthe light-shielding colored layer of the frame portion is formed on thewhole colored layer which becomes the reflection controlling layer inthe photolithography process for forming the light-shielding coloredlayer for the black matrix.

The display device of the present invention is a display device whichuses a color filter forming substrate for a display device and comprisesa transparent substrate as a base material; and, on one side of the basematerial, colored layers of respective colors for a color filterdisposed in a region for display and a frame portion comprising alight-shielding colored layer disposed as a region not for displayaround a periphery of the region for display, wherein the color filterforming substrate according to any of the above-mentioned descriptionsis used.

(Function)

Being constituted as described above, the color filter forming substrateof the present invention, when, in a display device, a frame portion isdisposed surrounding the respective colored layers for the color filterof the color filter forming substrate used and a non-display area isformed by the frame portion around a whole boundary between the displayarea and a frame, makes it possible to provide a color filter formingsubstrate which shows, when display is turned off, only a smalldifference between the display area and the frame portion which is thenon-display area surrounding the display area.

Especially, the present invention is effective for a display portionsuch as one in a multifunctional terminal, which requires high qualityand good design characteristics.

Specifically, the present invention achieves the above-mentionedfunction by providing a color filter forming substrate comprising: atransparent substrate as a base material; and, on one side of the basematerial, colored layers of respective colors for a color filterdisposed in a region for display and a light-shielding frame portiondisposed as a region not for display around outside of the region fordisplay, and the color filter forming substrate is used for a displaydevice, wherein the frame portion has a reflection controlling layer anda light-shielding colored layer laminated in this order from the basematerial side.

That is, by having a reflection controlling layer disposed between thebase material and the light-shielding colored layer which are placed ina direction perpendicular to the region for display, reflection ofoutside light on the light-shielding colored layer in the region not fordisplay can be controlled.

The above-mentioned reflection controlling layer includes a coloredlayer and, especially when the colored layer which is the reflectioncontrolling layer comprises at least one of the colored layers ofrespective colors for the color filter, the reflection controlling layercan be formed with the colored layer without increasing the number ofprocesses in a usual manufacturing process of a color filter substrate.

Further, when the reflection controlling layer is formed with a coloredlayer for a color filter of the color filter forming substrate, theremay be mentioned a first embodiment wherein the reflection controllinglayer has the same one colored layer disposed as a single layer, asecond embodiment wherein the reflection controlling layer has aplurality of different colored layers disposed in parallel as a singlelayer, and a third embodiment where the reflection controlling layer hasa plurality of different colored layers disposed as a laminate. However,the present invention is not limited to these.

Effect of the Invention

As described above, when, in a display device, a frame portion isdisposed surrounding the respective colored layers for the color filterof the color filter forming substrate used and a non-display area isformed by the frame portion around a whole boundary between the displayarea and a frame, the present invention makes it possible to provide adisplay device which shows, when the display is turned off, only a smalldifference between the display area and the frame portion which is thenon-display area surrounding the display area.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a plan view of the first example of the embodiments of thecolor filter forming substrate of the present invention; FIG. 1B andFIG. 10 are views taken in the direction of arrows along A1-A2 andA3-A4, respectively; FIG. 1D is an enlarged view of the A5 portion ofFIG. 1A; and FIG. 1E is an enlarged view of the A6 portion of FIG. 1A.

FIG. 2A is a plan view of the second example of the embodiments of thecolor filter forming substrate of the present invention; FIG. 2B andFIG. 2C are views taken in the direction of arrows along B1-B2 andB3-B4, respectively; FIG. 2D is an enlarged view of the B5 portion ofFIG. 2A; and FIG. 2E is an enlarged view of the B6 portion of FIG. 2A.

FIG. 3A is a plan view of the third example of the embodiments of thecolor filter forming substrate of the present invention; FIG. 3B andFIG. 3C are views taken in the direction of arrows along C1-C2 andC3-C4, respectively; FIG. 3D is an enlarged view of the C5 portion ofFIG. 3A; and FIG. 3E is an enlarged view of the C6 portion of FIG. 3A.

FIG. 4A is a figure showing reflectance of respective colored layers ina visible region (wavelength range of 400 nm to 700 nm); and FIG. 4B isa schematic view showing a method of measuring reflectance.

FIG. 5 is a figure showing reflected light from respective coloredlayers in an x-y representation of a CIE chromaticity diagram, asmeasured with illuminant C.

FIG. 6A is a plan view of a conventional color filter forming substrate;FIG. 6B and FIG. 6C are views taken in the direction of arrows alongE1-E2 and E3-E4, respectively; FIG. 6D is an enlarged view of the E5portion of FIG. 6A; and FIG. 6E is an enlarged view of the E6 portion ofFIG. 6A.

FIG. 7 is a plan view of a tablet-type multifunctional terminal usingthe color filter forming substrate shown in FIGS. 6A to 6E.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The color filter forming substrate of the present invention will bedescribed. The color filter forming substrate of the present inventioncomprises: a transparent substrate as a base material; and, on one sideof the base material, colored layers of respective colors for a colorfilter disposed in a region for display and a light-shielding frameportion disposed as a region not for display around outside of theregion for display, and the color filter forming substrate is used for adisplay device, wherein the frame portion has a reflection controllinglayer and a light-shielding colored layer laminated in this order fromthe base material side.

According to the present invention, in a display device, when a frameportion is disposed surrounding a periphery of respective colored layersfor a color filter of the color filter forming substrate used and anon-display area is formed by the frame portion around a whole boundarybetween the display portion and a frame, and the frame portion beingconstituted by laminating a reflection controlling layer and alight-shielding colored layer in this order from the base material side,it becomes possible to provide a color filter forming substrate whichshows only a small difference between the display area and the region ofthe frame portion which is a non-display area surrounding the displayarea when display is turned off.

Here, when a conventional color filter forming substrate is used for adisplay device, there is a problem that, when a power source (display)of the display device is turned off, a difference between the displayarea and the region of the frame portion which is a non-display areasurrounding the display area, more specifically a phenomenon that thenon-display area appears brighter than the display area, diminishesvisual quality of the display device itself.

The present inventors conducted diligent research on reasons why such aproblem arises and, as a result, found that the above-mentioneddifference between the display area and the non-display area arisesbecause reflectance of the frame portion comprising a light-shieldingcolored layer formed in the non-display area is higher than reflectanceas an average (hereinafter, may sometimes be referred to as “coloraverage”) of the colored layers of respective colors for a color filterformed in the display area. Having acquired this knowledge, the presentinventors further conducted research diligently and found that theproblem could be solved by forming in the frame portion a reflectioncontrolling layer between the base material and the light-shieldingcolored layer for the purposes of controlling reflectance-wavelengthcharacteristics (reflectance spectroscopic characteristics) of thelight-shielding colored layer and reducing the difference in reflectionof outside light between the color average and the light-shieldingcolored layer. Based on this finding, the present invention wascompleted.

As mentioned above, the color filter forming substrate of the presentinvention can exhibit the above-mentioned effect due to the frameportion having the reflection controlling layer. Hereinafter, thereflection controlling layer will be described in more detail.

The reflection controlling layer in the present invention refers to alayer which is designed to control reflectance-wavelengthcharacteristics (reflectance spectroscopic characteristics) of thelight-shielding colored layer and to decrease the difference inreflection of outside light between the color average and thelight-shielding colored layer.

Here, as a specific difference in reflection of outside light betweenthe color average and the light-shielding colored layer, especiallyeasily recognized is the difference between color average brightness ofthe reflected outside light (hereinafter, sometimes referred to as“color average brightness”) in the display area and brightness ofreflected outside light from the frame portion (hereinafter, referred toas “brightness of the frame portion”) in the non-display area.

Therefore, the reflection controlling layer is not particularly limitedas long as it can reduce reflectance of the light-shielding coloredlayer so that, at least, the difference between the color averagebrightness in the display area and the brightness of the frame portionin the non-display area can be decreased. More specifically, theabove-mentioned reflection controlling layer is preferably one which candecrease reflectance of the light-shielding colored layer so that anabsolute value of the above-mentioned difference (ΔY) in brightness (Yvalues) between the color average and the frame portion can be adjustedto 1.5 or less, above all 1 or less, and especially less than 1. This isso because, when the above-mentioned difference exceeds theabove-mentioned range, there is a possibility that it becomes difficultto reduce parallax between the display area and the non-display areaeven when the reflection controlling layer is formed between the basematerial and the light-shielding colored layer.

In addition, the method for measuring color average brightness andbrightness of the frame portion will be described later.

Furthermore, the above-mentioned difference between the display area andthe non-display area is influenced not only by the above-mentioneddifference in brightness between the color average in the display areaand the frame portion in the non-display area but also by a differencein tint of the reflected light of the above-mentioned color average(hereinafter, may sometimes be referred to as “color average tint”) andtint of the reflected light from the frame portion (hereinafter,sometimes referred to as the “tint of the frame portion”). Therefore,the reflection controlling layer in the present invention is morepreferably one which can decrease the difference in brightness betweenthe color average and the frame portion while also can decrease theabove-mentioned difference in tint of the color average and the frameportion.

Specific tint of the reflection controlling layer is not particularlylimited as long as the above-mentioned parallax between the display areaand the non-display area can be decreased; more specifically, theabove-mentioned difference in tint of the color average and the frameportion, namely absolute values of differences (Δx, Δy) of respectivecomponents of color coordinates (x, y) in the XYZ color coordinatesystem according to JIS 28701 can preferably be adjusted as follows: forΔx, 0.100 or less, above all 0.050 or less, and especially 0.020 orless; and for Δy, 0.100 or less, above all 0.050 or less, and especially0.020 or less.

This is so because, when the absolute values of the differences ofrespective components of the above-mentioned color coordinates exceedsthe above-mentioned range or when the above-mentioned difference is lessthan the above-mentioned range, there is a possibility that it becomesdifficult to reduce parallax between the display area and thenon-display area even when a reflection controlling layer is formedbetween the base material and the light-shielding colored layer.

In addition, the method for measuring the color coordinates of the coloraverage and the color coordinates of the frame portion will be describedlater.

Such a reflection controlling layer as described above is notparticularly limited as long as it can at least possess theabove-mentioned brightness. However, it is preferably a colored layer,and especially, the colored layer, which is the reflection controllinglayer, more preferably comprises at least one of the colored layers ofrespective colors for a color filter. This is so because, this way, itis possible to simplify a manufacturing process of a color filterforming substrate. Also, the above-mentioned reflection controllinglayer may be disposed separately by using a layer different fromrespective layers used for the color filter forming substrate.

When the reflection controlling layer is formed with the colored layersfor a color filter of the color filter forming substrate, the reflectioncontrolling layer may be one constituted by a colored layer of onecolor, one constituted by disposing a plurality of different coloredlayers in parallel as a single layer, or one constituted by disposing aplurality of different colored layers as a laminate. Above all, in thepresent invention, the reflection controlling layer is preferably oneconstituted by disposing a plurality of different colored layers inparallel as a single layer. By having the reflection controlling layerconstituted as described above, it becomes possible to suitably adjustboth brightness and tint of the color average in the display area, andthose of the frame portion in the non-display area.

Hereinafter, embodiments of the color filter forming substrate of thepresent invention will be described with reference to three embodimentsas examples. Specifically, there will be described a first embodimentwherein a reflection controlling layer is disposed as a single layer ofthe same one colored layer, a second embodiment wherein the reflectioncontrolling layer is formed by disposing a plurality of differentcolored layers in parallel as a single layer, and a third embodimentwhere the reflection controlling layer is disposed as a laminate of aplurality of different colored layers.

First of all, the first example of embodiments of the color filterforming substrate of the present invention will be described based onFIGS. 1A to 1E.

The color filter forming substrate 10 of the first example comprises: atransparent substrate as a base material 11; and, on one side of thebase material 11, colored layers (13R, 13G, and 13B) of respectivecolors for a color filter and a colored layer 13M for a black matrix ina region for display 13S and a light-shielding frame portion 12 as aregion not for display around outside the region for display 13S; andthe color filter forming substrate 10 is used for a display device,wherein the frame portion 12 has a reflection controlling layer 12 a 1and a light-shielding colored layer 12 b laminated in this order fromthe base material 11 side.

Further, a protective layer 14 (also referred to as “overcoat layer” or“OC layer”) is disposed evenly so as to cover the colored layer 13 inthe region for display 13S and the frame portion 12.

Here, the region for display 13S refers to a region which becomes adisplay area when used for a display device and means the region insidethe frame portion 12 in FIG. 1A.

Further, a region of the frame portion 12 which does not become thedisplay area is referred to as a region not for display.

Furthermore, the colored layer 13 refers collectively to the coloredlayers 13R, 13G, and 13B of respective colors for the color filter, andthe colored layer 13M for the black matrix.

In the first example, as shown in FIG. 1D, the reflection controllinglayer 12 a 1 is formed as a single layer with the red colored layer 13Rfor the color filter. Meanwhile, the light-shielding colored layer 12 bis formed as a single layer with the colored layer 13M for forming theblack matrix.

The red colored layer 13R of the reflection controlling layer 12 a 1 isformed in a photolithography process when the red colored layer 13R inthe region for display 13S is formed. Also, the light-shielding coloredlayer 12 b on the reflection controlling layer 12 a 1 is formed in aphotolithography process when the light-shielding colored layer 13M forthe black matrix in the region for display 13S is formed.

Additionally, in the region for display, as shown in FIG. 1E, thecolored layers 13R, 13G, and 13B of respective colors for the colorfilter are formed in a prescribed arrangement such that they areseparated by the colored layer 13M for forming the black matrix.

The shape of an aperture pattern of the black matrix and the arrangementof the colored layers of respective colors are not limited toembodiments shown in FIG. 1E.

There may also be mentioned a black matrix in which the shape of anaperture pattern is striped or the arrangement of the colored layers ischanged.

In the first example, by having a reflection controlling layer 12 a 1disposed between the base material 11 and the light-shielding coloredlayer 12 b which are arranged in a direction perpendicular to the regionfor display 13S, reflection of outside light on the light-shieldingcolored layer 12 b in the region not for display can be controlled.

Next, materials for each part will be described.

<Base Material 11>

As the base material 11 comprising a transparent substrate used in thefirst example, there can be used those which have been conventionallyused for the color filter forming substrate. Examples may be inflexibletransparent inorganic substrates such as silica glass, Pyrex (registeredtrademark) glass and a synthetic silica board; and flexible transparentresin substrates such as a transparent resin film and an optical resinboard. However, especially, it is preferable to use inorganic substratesand, among the inorganic substrates, it is preferable to use the glasssubstrates.

Furthermore, among the above-mentioned glass substrates, it ispreferable to use a non-alkali type glass substrate.

This is so because the non-alkali type glass substrate is excellent insize stability and in workability at high temperature heating treatmentand is free from any alkali component in the glass, making it possibleto be used suitably for a color filter forming substrate for a colorliquid crystal display device driven by an active matrix system.

AS the above-mentioned base material, transparent substrates are usuallyused.

<Light-Shielding Colored Layer 13M for Black Matrix and Frame Portion>

The light-shielding colored layer in the present invention is notparticularly limited as long as it can shield light which exits from thedisplay device to the outside when the color filter forming substrate ofthe present invention is used for a display device. However,specifically, its OD (Optical Density) value is preferably 2.5 or more,above all 3.0 or more, and especially 4.0 or more. In addition, theupper limit thereof is about 5.0.

Meanwhile, the above-mentioned OD value can be obtained, for example, byusing a method comprising measuring color by a spectrophotometriccolorimeter and calculating the OD value from a Y value of separatedlight. As an example of the spectrophotometric colorimeter, there can beused a spectrophotometric colorimeter manufactured by OlympusCorporation.

As such a light-shielding colored layer as described above, a black oneis usually used.

More specifically, the light-shielding colored layer 13M includes, forexample, a composition which comprises a black colorant dispersed ordissolved in a binder resin.

The composition which comprises the black colorant dispersed ordissolved in the binder resin can be made relatively thick in filmthickness.

The film thickness of the light-shielding colored layer 13M is set atabout 0.5 μm to 2 μm when it is a composition which comprises the blackcolorant dispersed or dissolved in the binder resin.

When a photolithography method is used as a method to form thelight-shielding colored layer 13M, there is used, as the binder resin, aphotopolymer resin having a reactive vinyl group such as an acrylatetype, a methacrylate type, a polyvinyl cinnamate type, a cyclized rubbertype, and the like.

In this case, to the photopolymer resin composition comprising a blackcolorant and a photopolymer resin for forming a black matrix(light-shielding colored layer), there may be added aphotopolymerization initiator, and if necessary, there may be furtheradded a sensitizer, a coating property improver, a development improver,a crosslinking agent, a polymerization inhibitor, a plasticizer, a flameretardant, and the like.

In addition, when a printing method or an inkjet method is used as amethod for forming the light-shielding colored layer 13M, the binderresin includes, for example, a polymethyl methacrylate resin, apolyacrylate resin, a polycarbonate resin, a polyvinyl alcohol resin, apolyvinyl pyrrolidone resin, a hydroxyethyl cellulose resin, acarboxymethyl cellulose resin, a polyvinyl chloride resin, a melamineresin, a phenol resin, an alkyd resin, an epoxy resin, a polyurethaneresin, a polyester resin, a maleic acid resin, a polyamide resin and thelike.

<Colored Layers 13R, 13G, and 13B>

In the present example, the colored layers of respective colors for thecolor filter comprise the colored layers of three colors, namely a redcolored layer 13R, a green colored layer 13G, and a blue colored layer13B.

The colored layers of respective colors are compositions havingcolorants such as pigments and dyes which are dispersed or dissolved inbinder resins and are formed by a photolithography method.

As the binder resin for the above-mentioned colored layers, there isused a photopolymer resin having a reactive vinyl group such as anacrylate type, a methacrylate type, a polyvinyl cinnamate type and acyclized rubber type.

In this case, to the photopolymer resin composition comprising acolorant and a photopolymer resin for forming the colored layer, theremay be added a photopolymerization initiator, and if necessary, theremay be further added a sensitizer, a coating property improver, adevelopment improver, a crosslinking agent, a polymerization inhibitor,a plasticizer, a flame retardant, and the like.

The film thickness of the above-mentioned colored layers of respectivecolors is usually set in a range of about 1 μm to 5 μm.

The colors of the colored layers are not particularly limited as long asthey include at least three colors of red, green, and blue. For example,the colors may include three colors of red, green, and blue; four colorsof red, green, blue, and yellow; and five colors of red, green, blue,yellow, and cyan.

Further, the colorant used for the red (also described as R) coloredlayer includes, for example, perylene-type pigments, lake pigments,azo-type pigments, quinacridone-type pigments, anthraquinone-typepigments, anthracene-type pigments, and isoindoline-type pigments.

These pigments may be used alone or as a mixture of two or more thereof.

The colorant used for the green (also described as G) colored layerincludes, for example, phthalocyanine-type pigments such aspolyhalogenated phthalocyanine-type pigments or polyhalogenated copperphthalocyanine-type pigments; triphenylmethane-type basic dyes; andisoindoline-type pigments; isoindolinone-type pigments.

These pigments and dyes may be used alone or as a mixture of two or morethereof.

The colorant used for the blue (also described as B) colored layerincludes, for example, copper phthalocyanine-type pigments,anthraquinone-type pigments, indanthrene-type pigments, indophenol-typepigments, cyanine-type pigments, and dioxazine-type pigments.

These pigments may be used alone or as a mixture of two or more thereof.

<Protective Layer 14>

The material for the protective layer includes a thermosetting resincomposition and a photocurable resin composition.

The photocurable resin composition is preferable for cutting a colorfilter forming substrate into respective pieces after imposition andfabrication.

As the photocurable resin composition for the protective layer, there isused one similar to the above-mentioned binder resins used for thecolored layers of respective colors for the color filter such as aphotopolymer having a reactive vinyl group of an acrylate type, amethacrylate type, a polyvinyl cinnamate type, or a cyclized rubbertype.

In this case also, there may be added, to the photopolymer resincomposition for forming the protective layer comprising a photopolymer,a photopolymerization initiator and if necessary, there may be furtheradded a sensitizer, a coating property improver, a development improver,a crosslinking agent, a polymerization inhibitor, a plasticizer, a flameretardant, and the like.

In the first example, the color filter forming substrate is coated withthe resin composition by a spin coating method after imposition andformation of respective colored layers 13R, 13G, 13B, 13M, and the frameportion 12. Hereat, a cut is formed on the protective layer between eachcolor filter forming substrate and the substrate is separated intoindividual pieces at the cut. For this purpose, the resin compositionfor the protective layer prepared as a photocurable resin composition iscoated and thereafter dried. This is followed by selectivephoto-irradiation of a prescribed region only and development to formthe protective layer. However, the method for forming the protectivelayer is not limited to this.

The thermosetting resin composition for the protective layer includesone using an epoxy compound and one using a thermal radical generator.

The epoxy compound includes heretofore known polyvalent epoxy compoundswhich can be cured by carboxylic acids, amine-type compounds, and thelike. Such epoxy compounds are widely disclosed in, for example, MasakiSimpo Ed., “Epoxy Resin Handbook,” Nikkan Kogyo Shinbun, Ltd. (1987) andthe like, and it is possible to use these compounds.

The thermal radical generator is at least one selected from the groupconsisting of persulfate salts, halogens such as iodine, azo compounds,and organic peroxides; and, azo compounds or organic peroxides are morepreferable.

The azo compounds includes 1, 1′-azobis(cyclohexane-1-carbonitrile),1-[(1-cyano-1-methylethyl)azo]formamide,2,2′-azobis[N-(2-propenyl)-2-methylpropionamide],2,2′-azobis(N-butyl-2-methylpropionamide), and2,2′-azobis(N-cyclohexyl-2-methylpropionamide), and the like. Theorganic peroxides include di(4-methylbenzoyl) peroxide,t-butylperoxy-2-ethyl hexanate, 1,1-di(t-hexylperoxy)cyclohexane,1,1-di(t-butylperoxy)cyclohexane, t-butylperoxy benzoate,t-butylperoxy-2-ethylhexyl monocarbonate, t-butyl-4,4-di(t-butylperoxy)butanate, dicumyl peroxide, and the like.

Further, the reflection controlling layer 12 a 1 will be described.

By using curable resin compositions of respective colors mentioned inExample 1, the colored layers of respective colors 13R, 13G, 13B, and13M were formed by a photolithography method in the same manner as inExample. When reflectance of each layer and the base material wasmeasured, reflectance-wavelength characteristics (reflectancespectroscopic characteristics) were obtained as shown in FIG. 4A.

Further, the graphs 13R, 13G, 13B, 13M, and 115 in FIG. 4A show thereflectance-wavelength characteristics (reflectance spectroscopiccharacteristics) of the red colored layer, the green colored layer, theblue colored layer, the light-shielding colored layer for the blackmatrix, and the base material, respectively. Measurement of thereflectance was carried out as shown in FIG. 4B by using a microspectrodevice OSP-SP2000™ (manufactured by Olympus Corporation).

First, a colored layer 13A for measurement is formed on a base material11 for measurement, followed by fabrication of a color filter formingsubstrate for measurement having the colored layer 13A for measurementand a black plate 30 for measurement disposed with an oil 20 forrefractive index adjustment interposed therebetween. Then, reflectancewas measured by irradiating the base material side of the color filterforming substrate for measurement with inspection light 45 and detectingreflected light of the inspection light 45 by a detector 40.

Furthermore, the reflectance 115 of the base material can be measured byusing a test piece prepared by disposing the base material formeasurement on a black plate for measurement with the oil for refractiveindex adjustment interposed therebetween.

And when the measured reflectance-wavelength data were represented interms of chromaticity coordinates (x, y) and brightness Y in the XYZcolor coordinate system according to JIS 28701 as measured by usingilluminant C, the results came out as shown in Table 1.

The color-average chromaticity coordinates (x, y) and brightness Y ofreflected light from respective colored layers 13R, 13G, and 13B for thecolor filter are (0.306, 0.321) and 1.36, respectively.

And when the chromaticity coordinates (x, y) in the XYZ color coordinatesystem according to JIS 28701 as measured by using illuminant C arecalculated based on the measured reflection-wavelength data, the resultsbecome as shown in FIG. 5.

The point marked “x” in the graph of FIG. 5 shows chromaticity (x, y) ofa color obtained by averaging reflected lights from the colored layersof respective colors of red, green, and blue for a color filter.

From the above, when the above-mentioned colored layers are used in thefirst example, it can be seen that the chromatic coordinates (x, y) andthe brightness Y of the color average in the region for display, wherethe respective colored layers 13R, 13G, and 13B for a color filter areformed, become approximately (0.306, 0.321) and 1.36, respectively.

In addition, the chromaticity coordinates (x, y) and the brightness Y ofthe light-shielding colored layer 12 b in the frame portion 12 become(0.323, 0.333) and 2.79, respectively.

Therefore, when respective colored layers similar to those in Exampleare used and if the brightness Y in the frame portion 12 is lowered sothat it becomes closer to 1.36, the above-mentioned color-averagebrightness, the difference in reflection of outside light between theabove-mentioned color average and the light-shielding colored layer 12 bbecomes smaller.

Based on these findings, it is the reflection controlling layer 12 a 1which was disposed in order to control the reflectance-wavelengthcharacteristics of the light-shielding colored layer 12 b and reduce thedifference in reflection of outside light between the above-mentionedcolor average and the light-shielding colored layer 12 b.

Here, the reflection controlling layer 12 a 1 means a layer forcontrolling the reflectance-wavelength characteristics (reflectancespectroscopic characteristics) of the light-shielding colored layer 12 band reducing the difference in reflection of outside light between theabove-mentioned color average and the light-shielding colored layer 12b.

TABLE 1 x y Y (1) Red colored layer 0.369 0.335 0.46 (2) Green coloredlayer 0.280 0.367 1.12 (3) Blue colored layer 0.305 0.301 2.49 (4) Coloraverage of the red, 0.306 0.321 1.36 green, and blue colored layers (5)Light-shielding colored 0.323 0.333 2.79 layer

On the other hand, it can be seen from Table 1 that the brightness Y ofthe red colored layer 13R is as small as 0.46.

The present inventors paid attention to this and envisioned that, whenthe frame portion is formed (see FIGS. 1A to 1E) by laminating thelight-shielding colored layer 12 b and the red colored layer 13R fromthe side of the base material 11, the reflectance of the frame portionmight be reduced compared to the conventional case (see FIGS. 6A to 6E)where the frame portion comprises a single layer of the light-shieldingcolored layer 12 b. In fact, when the red colored layer 13R and thelight-shielding colored layer 12 b were laminated in this order from theside of the base material 11, reflectance-wavelength data thereof showedthat the brightness Y was about 2.0, making it clear that the redcolored layer 13R is effective as the reflection controlling layer.

Based on these findings, the first example has the red colored layer 13Rdisposed between the light-shielding colored layer 12 b and the basematerial 11 as the reflection controlling layer.

In addition, in the first example, the red colored layer 13R in theregion for display 13S and the red colored layer 13R between thelight-shielding colored layer 12 b and the base material 11 in the frameportion 12 are formed by the same one photolithography process. Thus,the color filter forming substrate can be fabricated with the samenumber of processes as in the conventional case (see FIGS. 6A to 6E) inwhich the reflection controlling layer is not disposed.

Further, the colored layer used as the reflection controlling layer isnot particularly limited as long as it is one which is used as thecolored layer for the color filter in the region for display, and it ispossible to use any of three colored layers of red, green and blue, or,when four or more colored layers are used, any one colored layer chosenfrom the four or more colored layers. In the present invention, from thestandpoint of reducing the difference in tint between the color averagein the display area and the frame portion in the non-display area, it ispreferable to use the blue colored layer as the above-mentionedreflection controlling layer.

When a conventional color filter forming substrate is used for a displaydevice, there is a problem that tint of a non-display area having aframe portion constituted only of a light-shielding colored layer tendsto take on a yellowish color compared to the tint of a display area.Therefore, by using a blue colored layer as a reflection controllinglayer, it becomes possible to suppress a trouble that the tint of thenon-display area takes on a yellowish color and reduce a difference intint between the display area and the non-display area.

Next, a second example of embodiments of the color filter formingsubstrate of the present invention will be described based on FIGS. 2Ato 2E.

As in the first example, the color filter forming substrate 10 of thesecond example also comprises: a transparent substrate as a basematerial 11; and, on one side of the base material 11, colored layers(13R, 13G, and 13B) of respective colors for a color filter and acolored layer 13M for a black matrix in region for a display 13S and alight-shielding frame portion 12 as a region not for display aroundoutside of the region for display 13S; and the color filter formingsubstrate 10 is used for a display device, wherein the frame portion 12has a reflection controlling layer 12 a 2 and a light-shielding coloredlayer 12 b laminated in this order from the base material 11 side.

Further, a protective layer 14 (also referred to as “overcoat layer” or“OC layer”) is disposed evenly so as to cover the colored layer 13(collective term for the respective colored layers 13R, 13B, and 13B forthe color filter and the colored layer 13M for the black matrix) in theregion for display 13S and the frame portion 12.

In the second example, as is shown in FIG. 2D, the reflectioncontrolling layer 12 a 2 is formed by disposing three different coloredlayers 13R, 13G, and 13B in parallel as a single layer.

In the second example, the colored layers 13R, 13G, and 13B ofrespective colors for the reflection controlling layer 12 a 2 arerespectively formed in photolithography processes for forming thecolored layers 13R, 13G, and 13B of respective colors in the region fordisplay 13S. Also, the light-shielding colored layer 12 b of thereflection controlling layer 12 a 2 is formed in a photolithographyprocess when forming the light-shielding colored layer 13M for the blackmatrix in the region for display 13S.

In addition, effectiveness of the second example in controlling theabove-mentioned reflection of outside light is sometimes inferior to thefirst example.

Except the above-mentioned reflection controlling layer 12 a 2,respective parts are the same as in the first example and explanationsthereof will be omitted here.

In the second example, the red colored layer 13R, the green coloredlayer 13G, and the blue colored layer 13B of the reflection controllinglayer 12 a 2 are respectively formed in the photolithography processesof the red colored layer 13R, the green colored layer 13G, and the bluecolored layer 13B in the region for display 13S. Thus, the color filterforming substrate can be prepared by the same number of processes as inthe conventional case (see FIGS. 6A to 6E) in which the reflectioncontrolling layer is not disposed.

In the second example also, by having the reflection controlling layer12 a 2 disposed between the base material 11 and the light-shieldingcolored layer 12 b which are arranged in a direction perpendicular tothe region for display 13S, reflection of outside light on thelight-shielding colored layer in the region not for display can becontrolled.

The reflection controlling layer in the second example is notparticularly limited as long as it is constituted by disposing coloredlayers of three colors of red, green, and blue in parallel, and linewidths of respective colored layers and pitch (the width of the coloredlayers of three colors, which includes the width of spaces when thespaces are disposed between the colored layers) can suitably be selecteddepending on the intended use of the colored filter. Disposition of thecolored layers constituting the reflection controlling layer may be thesame as or different from disposition of the colored layers for thecolor filter formed in the region for display. Also, the boundaries ofthe respective colored layers may be partly overlapping or therespective colored layers may be disposed in parallel with prescribedspaces therebetween.

In the second example, from the standpoint of making smaller thedifference in tint between the color average in the region for displayand the frame portion in the region not for display, the line widths andthe pitch of the colored layers of respective colors of the reflectioncontrolling layer are preferably equivalent to the line width and thepitch of the colored layers for the color filter formed in the regionfor display. Also, in this case, it is more preferable that alight-shielding colored layer is formed between the respective coloredlayers in the reflection controlling layer. This can make theabove-mentioned difference in tint between the color average and theframe portion even smaller.

On the other hand, in the reflection controlling layer in the secondexample, the difference in brightness between the color average in theregion for display and the frame portion in the region not for displaycan be made even smaller by controlling the line widths of the coloredlayers.

Here, as shown in the above-mentioned FIG. 4A, the blue colored layertends to show higher reflectance compared to the red colored layer andthe green colored layer. Therefore, for example, when a color filterforming substrate of the present invention is manufactured by way oftrial and if brightness of the above-mentioned color average is brighterthan that of the above-mentioned frame portion, the brightness (Y value)of the frame portion can be increased by increasing the line width, anarea ratio, and the like of the blue colored layer in the reflectioncontrolling layer. Thus, the difference in brightness between the coloraverage and the frame portion can be made smaller. On the other hand,when brightness of the color average is darker than that of the frameportion, the brightness (Y value) of the frame portion can be reduced bymaking smaller the line width, the area ratio, and the like of the bluecolored layer in the reflection controlling layer. Thus, the differencein brightness between the color average and the frame portion can bemade smaller.

Next, a third example of embodiments of the color filter formingsubstrate of the present invention will be described based on FIGS. 3Ato 3E.

As is the case in the first example and the second example, the colorfilter forming substrate of the third example also comprises: atransparent substrate as a base material 11; and, on one side of thebase material 11, colored layers (13R, 13G, and 13B) of respectivecolors for a color filter and a colored layer 13M for a black matrix ina region for display 13S and a light-shielding frame portion 12 as aregion not for display around outside of the region for display 13S; andthe color filter forming substrate 10 is used for a display device,wherein the frame portion 12 has a reflection controlling layer 12 a 3and a light-shielding colored layer 12 b laminated in this order fromthe base material 11 side.

Further, a protective layer 14 (also referred to as “overcoat layer” or“OC layer”) is disposed evenly so as to cover the colored layer 13(collective term for the colored layers (13R, 13G, and 13B) ofrespective colors for the color filter and the colored layer 13M for theblack matrix) in the region for display 13S and the frame portion 12.

In the third example, the reflection controlling layer 12 a 3 is formedby disposing three different colored layers 13R, 13G, and 13B as alaminate.

In the third example, the colored layers 13R, 13G, and 13B of respectivecolors for the reflection controlling layer 12 a 3 are respectivelyformed in the photolithography processes when forming the colored layers13R, 13G, and 13B of respective colors in the region for display 13S.Also, the light-shielding colored layer 12 b of the reflectioncontrolling layer 12 a 3 is formed in the photolithography process whenforming the light-shielding colored layer 13M for the black matrix inthe region for display 13S.

Except the above-mentioned reflection controlling layer 12 a 3,respective parts are the same as in the first example and explanationsthereof will be omitted here.

Furthermore, in the third example also, the red colored layer 13R, thegreen colored layer 13G, and the blue colored layer 13B of thereflection controlling layer 12 a 3 are respectively formed in thephotolithography processes of the red colored layer 13R, the greencolored layer 13G, and the blue colored layer 13B in the region fordisplay 13S. Thus, the color filter forming substrate can be prepared bythe same number of processes as in the conventional case (see FIGS. 6Ato 6E) in which the reflection controlling layer is not disposed.

In the third example also, by having the reflection controlling layer 12a 3 disposed between the base material 11 and the light-shieldingcolored layer 12 b which are arranged in a direction perpendicular tothe region for display 13S, reflection of outside light on thelight-shielding colored layer in the region not for display can becontrolled.

The present invention is not limited to the above-mentioned embodiments.

For example, in each of the above-mentioned first example to the thirdexample, there may also be mentioned an embodiment wherein a pluralityof spacers of prescribed height are further disposed in the region fordisplay on the protective layer 14.

In addition, a liquid crystal display device has a structure where acolor filter forming substrate having a black matrix layer comprising alight-shielding colored layer and colored layers of respective colorsdisposed on one side of a transparent substrate, and a counter electrodesubstrate (also referred to as “TFT substrate”) are disposed opposite toeach other with a prescribed space therebetween and having a liquidcrystal encapsulated in the space. Control of light transmittance ofpixels of the colored layers of respective colors is performed byelectrically controlling orientation of the liquid crystal and, in orderto control the space between the color filter forming substrate and thecounter electrode substrate (also referred to as “TFT substrate”) at aprescribed value, the liquid crystal display device has a configurationwhere a plurality of spacers of prescribed height are disposed on theprotective layer 14 of the color filter forming substrate.

Further, in each of the above-mentioned first example to the thirdexample, colored layers for the color filter as the reflectioncontrolling layer are used, but the colored layers for the reflectioncontrolling layer is not limited to these.

Furthermore, although colored layers are mentioned as the reflectioncontrolling layer, the reflection controlling layer is not limited tothe colored layers.

The reflection controlling layer is not limited to the colored layers aslong as it has a function as a reflection controlling layer and isapplicable to a display device in terms of quality.

Meanwhile, the display device of the present invention is notparticularly limited as long as it has the color filter formingsubstrate mentioned above and includes, for example, anelectroluminescence display device and the like, in addition to theabove-mentioned liquid crystal display.

The present invention is not limited to the above-mentioned embodiments.The above-mentioned embodiments are exemplifications, and any examplesthat have substantially the same constitution and demonstrate the samefunctions and effects as the technical concept described in claims ofthe present invention are included in the technical scope of the presentinvention.

EXAMPLES

The present invention will be further described with reference toExamples.

Example 1

Example 1 is preparation according to the first example of embodimentsshown in FIGS. 1A to 1E, comprising steps of, as described below,preparing a photocurable curable resin composition A; preparing, byusing the curable resin composition A prepared, a red curable resincomposition, a green curable resin composition, and a blue curable resincomposition for forming a color filter, and curable resin compositionsfor forming a black matrix and a frame portion; and carrying out, byusing these, photolithography processes for respective curable resincompositions to form respective colored layers for a color filter, andcolored layers for the black matrix and the frame portion.

Here, after forming a red colored layer 13R for the color filter in theregion for display 13S and a red colored layer 13R which becomes areflection controlling layer 12 a of the frame portion 12 by the sameone photolithography process, a green colored layer 13G and a bluecolored layer 13B for the color filter were each independently formed byone photolithography process and, thereafter, a light-shielding coloredlayer 13M for the black matrix and the frame portion was formed.

(Preparation of Curable Resin Composition A)

A polymerization tank was charged with 63 weight parts of methylmethacrylate (MMA), 12 weight parts of acrylic acid (AA), 6 weight partsof 2-hydroxyethyl methacrylate (HEMA), and 88 weight parts ofdiethyleneglycol dimethyl ether (DMDG). After stirring and dissolvingthe mixture, 7 weight parts of 2,2′-azobis(2-methylbutyronitrile) wereadded and dissolved homogeneously.

Thereafter, under a nitrogen flow, the mixture was stirred at 85° C. for2 hours and reacted further at 100° C. for 1 hour.

To the solution obtained was further added 7 weight parts of glycidylmethacrylate (GMA), 0.4 weight part of triethylamine, and 0.2 weightpart of hydroquinone, and the mixture was stirred at 100° C. for 5 hoursto obtain a copolymer resin solution (solid content, 50%).

Next, the following materials were stirred and mixed at room temperatureto obtain a curable resin composition.

<Composition of Curable Resin Composition>

-   -   The above-mentioned copolymer resin solution (solid content,        50%): 16 weight parts    -   Dipentaerythritol pentaacrylate (Sartomer Company Inc., SR399™):        24 weight parts    -   Orthocresol-novolac-type epoxy resin (Japan Epoxy Resins Co.,        Ltd., Epicoat 180S70™): 4 weight parts    -   2-Methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one: 4        weight parts    -   Diethylene glycol dimethyl ether: 52 weight parts

<Formation of Red Colored Layer 13R>

On a glass substrate (AN Material manufactured by Asahi Glass Co., Ltd)(substrate), a red curable resin composition of the followingcomposition was coated by a spin coating method and, subsequently, driedin an oven of 70° C. for 3 minutes.

Then, a photomask was placed at a distance of 100 μm from the coatedfilm of the red curable resin composition and, by using a proximityaligner, ultraviolet light was irradiated for 10 seconds only on aregion corresponding to a colored layer forming region by means of a 2.0kw ultra-high pressure mercury lamp.

Subsequently, the substrate was immersed in a 0.05 wt % aqueouspotassium hydroxide solution (liquid temperature, 23° C.) for 1 minuteto perform alkali development, whereby only an uncured portion of thecoated film of the red curable resin composition was removed.

Thereafter, the substrate was subjected to a heat treatment by beingallowed to stand in an atmosphere of 230° C. for 15 minutes to form apattern consisting of a red colored layer 13 in a region for display 13Sand all over a frame portion forming region which becomes a region notfor display.

The thickness of the formed film became 2.0 μm.

<Composition of Red Curable Resin Composition>

-   -   C.I. Pigment Red 177: 3 weight parts    -   C.I. Pigment Red 254: 4 weight parts    -   Polysulfonic acid-type polymeric dispersant: 3 weight parts    -   Curable resin composition A: 23 weight parts    -   3-Methoxybutyl acetate: 67 weight parts

<Formation of Green Colored Layer 13G>

Then, by using a green curable resin composition of the followingcomposition, a relief pattern consisting of a green colored layer wasformed in a region for display by a process similar to the formation ofthe red relief pattern with the thickness of the formed film beingadjusted to 2.0 μm.

<Composition of Green Curable Resin Composition>

-   -   C.I. Pigment Green 58: 7 weight parts    -   C.I. Pigment Yellow 138: 1 weight part    -   Polysulfonic acid-type polymeric dispersant: 3 weight parts    -   Curable resin composition A: 22 weight parts    -   3-Methoxybutyl acetate: 67 weight parts

(Formation of Blue Colored Layer 13B)

Further, using a blue curable resin composition of the followingcomposition, a blue relief pattern was formed in the region for displayby a process similar to the formation of the red relief pattern with thethickness of the formed film being adjusted to 2.0 μm.

<Composition of Blue Curable Resin Composition>

-   -   C.I. Pigment Blue 15:6: 5 weight parts    -   Polysulfonic acid-type polymeric dispersant: 3 weight parts    -   Curable resin composition A: 25 weight parts    -   3-Methoxybutyl acetate: 67 weight parts

(Formation of Light-Shielding Colored Layer 13M for Black Matrix andFrame Portion)

First, components of the following amounts were mixed and the mixturewas dispersed thoroughly by means of a sand mill to prepare a blackpigment dispersion.

<Composition of Black Pigment Dispersion>

-   -   Black pigment: 23 weight parts    -   Polymeric dispersant (BYK-Chemie Japan KK, Disperbyk 111™): 2        weight parts    -   Solvent (diethylene glycol dimethyl ether): 75 weight parts

Then, components of the following amounts were mixed thoroughly toobtain a light-shielding colored layer composition.

<Composition of Light-Shielding Colored Layer Composition>

-   -   Above-mentioned black pigment dispersion: 60 weight parts    -   Curable resin composition A: 20 weight parts    -   Diethylene glycol dimethyl ether: 30 weight parts

On a substrate having colored layers formed thereon, the above-mentionedlight-shielding colored layer composition was coated by a spin coaterand was dried at 100° C. for 3 minutes to form a light-shielding coloredlayer.

The light-shielding colored layer was exposed to a light-shieldingpattern using an ultra-high pressure mercury lamp. Subsequently, thesubstrate was developed with a 0.05 wt % aqueous potassium hydroxidesolution and, thereafter, the substrate was subjected to a heattreatment by being allowed to stand in an atmosphere of 230° C. for 30minutes to form a light-shielding colored layer 13M on the region fordisplay and the frame portion 12.

Here, the light-shielding colored layer was formed all over the redpattern in the region of the frame portion 12.

The thickness of the formed film after the heat treatment became 1.0 μm.

(Formation of Protective Layer 14)

On a substrate having the colored layer 13 formed as described above,the afore-mentioned curable resin composition A was coated by a spincoating method and dried to form a coated film of a dried thickness of 2μm.

A photomask was placed at a distance of 100 μm from the coated film ofthe curable resin composition A and, by using a proximity aligner,ultraviolet light was irradiated for 10 seconds only on a regioncorresponding to a protective layer forming region by means of a 2.0 kwultra-high pressure mercury lamp.

Subsequently, the substrate was immersed in a 0.05 wt % aqueouspotassium hydroxide solution (liquid temperature, 23° C.) for 1 minuteto perform alkali development, whereby only an uncured portion of thecoated film of the curable resin composition was removed.

Thereafter, the substrate was subjected to a heat treatment by beingallowed to stand in an atmosphere of 230° C. for 15 minutes to form aprotective layer.

In this way, the color filter forming substrate 10 of the first exampleshown in FIGS. 1A to 1E was prepared.

Then, spacers of prescribed height were disposed in the following way onthe protective layer 14 of the prepared color filter forming substrate10 of the first example and a liquid crystal display device wasfabricated.

(Formation of Spacers)

On the protective layer 14 of the color filter forming substrate 10having the colored layers and the protective layer formed as describedabove, the curable resin composition A was coated by a spin coatingmethod and dried to form a coated film.

A photomask was placed at a distance of 100 μm from the coated film ofthe curable resin composition A and, by using a proximity aligner,ultraviolet light was irradiated for 10 seconds only on a regioncorresponding to the spacer forming region by means a 2.0 kw ultra-highpressure mercury lamp.

Subsequently, the substrate was immersed in a 0.05 wt % aqueouspotassium hydroxide solution (liquid temperature, 23° C.) for 1 minuteto perform alkali development, whereby only an uncured portion of thecoated film of the curable resin composition A was removed.

Thereafter, the substrate was subjected to a heat treatment by beingallowed to stand in an atmosphere of 230° C. for 30 minutes so as toform spacers of prescribed number density.

(Fabrication of Liquid Crystal Display Device)

On the surface of the colored layer formed side of the color filterforming substrate obtained as described above, an oriented film(SE-6210™ manufactured by Nissan Chemical Industries, Ltd.) was formed.

Subsequently, a necessary amount of IPS liquid crystal was dropped ontoa glass substrate (TFT substrate) on which TFTs had been formed, and theabove-mentioned color filter was superposed. Using a UV curable resin(Three Bond 3025™ manufactured by ThreeBond Co., Ltd.) as a sealingmaterial, exposure was carried out with an irradiance level of 400mJ/cm² while applying a pressure of 0.3 kgf/cm² at room temperature tojoin the glass substrate and the color filter to form a cell, andpolarizing plates, a backlight unit, and a cover were placed to obtain aliquid crystal display device.

Example 2

Except that the red colored layer 13R of the frame portion 12 in Example1 was changed to a green colored layer 13G, a liquid crystal displaydevice was fabricated in the same manner as in Example 1.

Example 3

Except that the red colored layer 13R of the frame portion 12 in Example1 was changed to a blue colored layer 13B, a liquid crystal displaydevice was fabricated in the same manner as in Example 1.

Example 4

Except that the red colored layer 13R of the frame portion 12 in Example1 was changed to a stripe pattern containing a red colored layer 13R, agreen colored layer 13G, and a blue colored layer 13B, a liquid crystaldisplay device was fabricated in the same manner as in Example 1 (referto the second example shown in FIGS. 2A to 2E).

Example 5

Except that a green colored layer 13G and a blue colored layer 13B werelaminated on the red colored layer 13R of the frame portion 12 inExample 1, a liquid crystal display device was fabricated in the samemanner as in Example 1 (refer to the third example shown in FIG. 3).

Example 6

Except that the order of formation of the red pattern and the greenpattern was reversed, a liquid crystal display device was fabricated inthe same manner as in Example 5.

Example 7

Except that the order of formation of the red pattern and the bluepattern was reversed, a liquid crystal display device was fabricated inthe same manner as in Example 5.

Example 8

Except that the red curable resin composition was changed as describedbelow, a liquid crystal display device was fabricated in the same manneras in Example 1.

<Composition of Red Curable Resin Composition>

-   -   C.I. Pigment Red 177: 4.5 weight parts    -   C.I. Pigment Red 254: 5.5 weight parts    -   Polysulfonic acid-type polymeric dispersant: 3 weight parts    -   Curable resin composition A: 20 weight parts    -   3-Methoxybutyl acetate: 67 weight parts

Comparative Example 1

Except that the red colored layer 13R was not formed in the frameportion 12, a liquid crystal display device was fabricated in the samemanner as in Example 1.

Each liquid crystal display device, fabricated as in the above-mentionedExample 1 to Example 8, and Comparative Example, was subjected tomeasurement of reflectance-wavelength characteristics (reflectionspectrometry) from the viewer's side when display was turned off byusing a microspectro device OSP-SP 2000™ (manufactured by OlympusCorporation). From the data obtained, there were obtained respectivecolor coordinates (x, y) and brightness Y in the XYZ color coordinatesystem according to JIS 28701 as measured by illuminant C.

The results came out as shown in Table 2.

TABLE 2 (Value in non-display Non-display area Display area area) −(Value in (frame portion) (open portion) display area) x y Y x y Y Δx ΔyΔY Evaluation Example 1 0.363 0.358 2.02 0.306 0.321 1.36 0.057 0.0370.66 ⊚ Example 2 0.321 0.363 2.41 0.306 0.321 1.36 0.015 0.042 1.05 ○Example 3 0.307 0.305 2.80 0.306 0.321 1.36 0.001 −0.016 1.44 ○ Example4 0.326 0.337 2.41 0.306 0.321 1.36 0.020 0.016 1.05 ○ Example 5 0.3600.361 1.03 0.306 0.321 1.36 0.054 0.040 −0.33 ⊚ Example 6 0.323 0.3621.43 0.306 0.321 1.36 0.017 0.041 0.07 ⊚ Example 7 0.312 0.308 1.830.306 0.321 1.36 0.006 −0.013 0.47 ⊚ Example 8 0.358 0.356 1.82 0.3040.321 1.33 0.054 0.036 0.49 ⊚ Comparative 0.322 0.336 3.10 0.306 0.3211.36 0.016 0.015 1.74 × Example 1 Evaluation criteria were: ⊚(Excellent), when the difference in Y value between the region fordisplay and the region not for display was less than 1.0; ○ (Good), whenthe difference was no less than 1.0 and no more than 1.5; and × (Poor),when the difference was more than 1.5.

REFERENCE NUMERALS

-   -   10: Color filter forming substrate    -   11: Base material (transparent substrate)    -   12: Frame portion    -   12 a 1, 12 a 2, 12 a 3: Reflection controlling layer    -   12 b: Light-shielding colored layer    -   13: Colored layer    -   13R: Red colored layer    -   13G: Green colored layer    -   13M: Colored layer for black matrix (also referred to as        “light-shielding colored layer”)    -   13B: Blue colored layer    -   13S: Region for display    -   13A: Colored layer (for measurement)    -   14: Protective layer (also referred to as “overcoat layer” or        “OC layer”)    -   20: Oil for refractive index adjustment    -   30: Black plate    -   40: Detector    -   45: Inspection light    -   110: Color filter forming substrate    -   111: Base material (transparent substrate)    -   112: Frame portion    -   113: Colored layer    -   113 s: Region for display    -   114: Protective layer (also referred to as “overcoat layer” or        “OC layer”)    -   120: Display device (also referred to as a tablet display device        or a multifunctional terminal)    -   121: Frame    -   122: Display area (also referred to as “colored layer forming        region for color filter”)    -   123: Non-display area (also referred to as “frame region”)

What is claimed is:
 1. A color filter forming substrate, comprising: atransparent substrate as a base material; and, on one side of the basematerial, colored layers of respective colors for a color filterdisposed in a region for display and a light-shielding frame portiondisposed as a region not for display around outside of the region fordisplay; and the color filter forming substrate is used for a displaydevice by being disposed to a viewer side of the display device, whereinthe frame portion has a reflection controlling layer and alight-shielding colored layer laminated in this order from the basematerial side, and the reflection controlling layer comprises aplurality of different colored layers disposed in parallel as a singlelayer.
 2. The color filter forming substrate according to claim 1,wherein the plurality of different colored layers include a red coloredlayer, a green colored layer, and a blue colored layer.
 3. A method formanufacturing a color filter forming substrate, the color filter formingsubstrate comprises: a transparent substrate as a base material; and, onone side of the base material, colored layers of respective colors for acolor filter disposed in a region for display and a light-shieldingframe portion disposed as a region not for display around outside of theregion for display; the color filter forming substrate is used for adisplay device by being disposed to a viewer side of the display device;the frame portion has, a colored layer for a reflection controllinglayer and a light-shielding colored layer laminated in this order fromthe base material side, and the reflection controlling layer comprises aplurality of different colored layers disposed in parallel as a singlelayer; wherein the colored layers of respective colors for the colorfilter, a light-shielding colored layer for a black matrix whichseparates the colored layers of respective colors, the colored layerwhich becomes the reflection controlling layer of the frame portion, andthe light-shielding colored layer of the frame portion are each formedby one photolithography process; the whole colored layer which becomesthe reflection controlling layer of the frame portion is formed in atleast one of the respective photolithography processes for forming thecolored layers of respective colors for the colored filter; and thelight-shielding colored layer of the frame portion is formed on thewhole colored layer which becomes the reflection controlling layer inthe photolithography process for forming the light-shielding coloredlayer for the black matrix.
 4. A display device using a color filterforming substrate for a display device, the color filter formingsubstrate comprises a transparent substrate as a base material; and, onone side of the base material, colored layers of respective colors for acolor filter disposed in a region for display and a frame portioncomprising a light-shielding colored layer disposed as a region not fordisplay around a periphery of the region for display, wherein the colorfilter forming substrate according to claim 1 is used.